JP2010190700A - Storage container level gauge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage container level gauge with a relatively simple structure always maintaining sensitivity of an antenna in a satisfactory state by suppressing dew condensation generated on the antenna and thereby accurately measuring the level of a content in the storage container. <P>SOLUTION: The storage container level gauge 4 includes: a control unit 5 having a function of transmitting and receiving a microwave or an ultrasonic wave; the antenna 6 emitting the microwave or the ultrasonic wave transmitted from the control unit 5 toward coal 3, receiving a reflection wave reflected by the coal 3, and causing the control unit 5 to receive it; and a support member 7 supporting the entire antenna 6 above a coal bunker 1 while being exposed to the atmosphere outside the coal bunker 1 above a measurement hole 1c of the coal bunker 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a level meter for a storage container that measures the storage amount (level) of contents in the storage container by microwaves or ultrasonic waves.

For example, when measuring the level of the contents in the storage container, such as measuring the amount of coal stored in the coal bunker, as described in Patent Document 1 and Patent Document 2, a micro-phone transmitted from the control unit is used. 2. Description of the Related Art Conventionally, a level meter configured to emit a wave, an ultrasonic wave, or the like to a content through a cone-shaped or parabolic antenna and cause a control unit to receive a microwave reflected by the content through the antenna is widely known.
In this type of level meter, the control unit arranged outside the storage container is operated with only the antenna inserted into the storage container from the measurement hole opened on the upper surface of the storage container. In the case of inclusions such as coal or coke with moisture in order to prevent ignition or cooling, the humidity in the storage container becomes extremely high. In many cases, condensation occurred due to moisture.

If condensation occurs on the antenna in this way, it interferes with the transmission and reception of microwaves, etc. by the antenna, so accurate level measurement is not only difficult, but the worst measurement itself may not be possible. there were.
In addition, when condensation occurs on the antenna, it increases the amount of dust in the storage container attached to the antenna, which lowers the sensitivity of the level meter and makes it impossible to perform accurate measurements. There was a possibility of shortening the service life.
On the other hand, in order to solve the above-mentioned problems of dew condensation and dust, it is conceivable that the moisture and dust in the storage container are mechanically forced out of the storage container. In addition to the extremely complicated structure, the manufacturing, operation and maintenance costs increase. In addition, as a measure against dust, it may be possible to prevent condensation or dust from adhering to the antenna by covering the antenna, but it is not possible to prevent condensation or dust from adhering to the cover itself. Although it can be expected for a long time, the decrease in antenna sensitivity itself cannot be suppressed, and in order to maintain the sensitivity, it is necessary to frequently replace the cover and there is a problem that the work is troublesome Therefore, it is not a fundamental solution for accurately measuring the level in the storage container.

JP 2006-38756 A JP 2006-214609 A

  The technical problem of the present invention is that it is relatively easy to accurately measure the content level in the storage container while keeping the sensitivity of the antenna always good by suppressing the dew condensation that occurs in the antenna. The object is to provide a level meter for a storage container of construction.

  In order to solve the above-mentioned problems, the level meter for a storage container according to the present invention is mounted on a storage container, and the storage level of the contents stored in the storage container is measured through a measurement hole provided in the storage container. A level meter for measuring, having a function of transmitting and receiving microwaves or ultrasonic waves, and emitting microwaves or ultrasonic waves transmitted from the control unit toward the contents, An antenna for receiving the reflected wave reflected and receiving it by the control unit; and a support member for supporting the whole antenna on the storage container in a state of being exposed to the atmosphere outside the storage container on the measurement hole. It is characterized by having.

In the present invention, the support member includes a plurality of upwardly extending columns arranged so as to surround the measurement hole, and an attachment plate that is attached to the upper ends of these columns and that fixes the antenna in a state of projecting downward. It can have.
In this case, it is preferable that the support member has a mesh member attached to each space between adjacent columns.

According to the present invention, the entire antenna is supported on the storage container while being exposed to the atmosphere outside the storage container on the measurement hole by the support member, and the entire antenna is always in contact with the air in the atmosphere. Because it is configured to naturally ventilate, condensation is much less likely to occur than when the antenna is placed in a storage container with high humidity. The level of the contents in the storage container can be accurately measured.
Moreover, since the antenna is exposed to the air outside the storage container and naturally ventilates, the configuration is much simpler than that when water is forced out of the storage container by a machine or the like, and the manufacturing cost is also suppressed. It is possible.

1 to 4 show an embodiment of the present invention. In this embodiment, the level meter for a storage container according to the present invention contains moisture as a content to prevent ignition. It shows an example where it is attached to a storage container for storing coal, that is, a coal bunker.
As shown in FIG. 2, this coal bunker 1 is formed in a cylindrical shape on the upper side and a tapered shape in a funnel shape from the middle to the lower, and a substantially horizontal upper surface 1a formed so as to close the upper part of the coal bunker 1. And a supply port 1b for supplying coal, from which the coal 3 is sequentially put into the coal bunker 1 by the belt conveyor 2 to store the coal 3, while a lower chute (not shown) ) To discharge the coal to a mill or the like, and is used for measuring the storage level of coal by the level meter 4 for the storage container separately from the supply port 1b for charging the coal on the upper surface portion. A measurement hole 1c is provided.

As shown in FIG. 1, the level meter 4 emits a control unit 5 having a function of transmitting and receiving microwaves and a microwave transmitted from the control unit 5 toward the coal 3 in the coal bunker 1. In addition, an antenna 6 that receives the reflected wave reflected by the coal 3 and a support member 7 that supports the antenna 6 outside the banger 1 are provided.
And this level meter 4 is attached on the upper surface part 1a of the said coal bunker 1, and by transmitting and receiving a microwave through the measurement hole 1c opened in the upper surface part 1a of this coal bunker 1, The storage level of the coal 3 inside the bunker 1 can be measured.

The control unit 5 is electrically connected to another control means (not shown), and the operation is constantly controlled and monitored by the control means.
More specifically, the control unit 5 includes a transmission means for transmitting microwaves and a calculation means for calculating the distance to coal based on the reflected wave received via the antenna, Data obtained by the calculation means can be transferred to the control means for data collection.
A waveguide 8 for transmitting and receiving microwaves is attached to the lower end of the control unit 5 and is used for connection with the antenna 6.

The antenna 6 is formed in a substantially conical cone shape that rises in the vertical direction and expands downward as it goes downward. The upper end of the antenna 6 is located below the control unit 5 via the waveguide 8. It is connected. More specifically, the antenna 6 is fixed to a mounting plate 11 (described later) of the support member 7 so as to protrude downward, and the microwave transmitted from the control unit 5 is directed vertically downward. On the other hand, when the emitted microwave is reflected by the coal stored and returned as a reflected wave, it has a function of receiving the reflected wave.
Further, a disk-like flange member 9 provided so as to protrude substantially horizontally toward the outside is attached to the upper end portion of the antenna 6, and is provided for attachment to the support member 7. Yes.
The flange member 9 has an outer diameter larger than the diameter of the lowermost end of the antenna 6, and has a form protruding outward from the antenna 6 in a front view or a bottom view.

The support member 7 is arranged to surround the measurement hole 1c opened in the coal bunker 1 and extends vertically upwards 10 and is attached to the upper ends of the support columns 10 so that the antenna 6 is made of a metal integrally provided with the above-described mounting plate 11 for fixing downward 6 in a state of protruding downward.
Specifically, each of the support columns 10 has an axial length sufficiently larger than the height of the antenna 6 and is substantially L-shaped in plan view and formed in the same shape and length. They are arranged so that their tops face outward and are positioned at the corners of a substantially square in plan view.
The mounting plate 11 is a disk-shaped member fixed to the upper end of each support column 10 so as to be substantially horizontal, and has a substantially circular mounting in plan view for mounting the antenna. The working hole 11a is opened so as not to interfere with the connecting portion of the support column 10. The mounting plate 11 is formed larger than the outer diameter of the flange member 9 attached to the antenna 6, while the mounting hole 11 a is formed smaller than the outer diameter of the flange member 9.
In addition, each said support | pillar 10 is connected with this attachment board 11 so that this attachment hole 11a may be enclosed in the center vicinity of the attachment board 11, and a load acts on each support | pillar 10 equally.

Then, the support member 7 of the antenna 6 is fixed to the mounting plate 11 after the antenna 6 is inserted into the mounting hole 11 a of the mounting plate 11 from the upper surface side to the lower surface side of the mounting plate 11. The peripheral edge portion on the lower surface side of the flange member 9 attached to the upper end portion of the antenna 6 is engaged with the peripheral edge portion of the attachment hole 11a in the attachment plate 11, and the flange member 9 and the attachment plate 11 are This is done by fixing the overlapping portion with a plurality of bolts (not shown).
As a result, the antenna 6 protrudes downward substantially at the center of the lower surface of the mounting plate 11 of the support member 7 in a state where the antenna 6 is exposed from the coal bunker 1 and exposed to the atmosphere on the measurement hole 1c as a whole. On the other hand, the control unit 5 is arranged substantially at the center on the upper surface side of the mounting plate 11.

  In this embodiment, the height of the antenna is about 240 mm, the diameter of the bottom end is about 95 mm, the diameter of the flange member is about 210 mm, and the axial length (height of the support member column) ) Is set to about 510 mm, the diameter of the mounting plate is set to about 710 mm, and the inner diameter of the mounting hole is set to about 170 mm. However, it goes without saying that each size can be changed as appropriate.

As shown in FIG. 3, a metal mesh member 12 (metal mesh) is attached to the support member 7 in each space between the adjacent support columns 10, and the antenna 6 is formed by these mesh members 12. It is a mode in which the four sides of the space surrounded by the support column 10 is covered.
By constituting in this way, while the antenna 6 is protected and large foreign matter is prevented from being mixed into the coal bunker 1 through the measurement hole 1c of the coal bunker 1 from the gaps between the columns, the mesh member Natural ventilation is performed in the space in which the antenna 6 is accommodated through the gap between the twelve lattices, and the ventilation to the antenna 6 is always kept in a good state. In addition, since the state of the antenna 6 can be visually inspected through the gaps between the lattices of the mesh member 12, further improvement in maintainability is achieved.
In this embodiment, the mesh member 12 is formed in a mesh shape on a frame member 12a having a substantially rectangular shape in front view that fits the size of each space between adjacent struts 10, and on the inner periphery of the frame member 12a. Further, the expanded metal (wire mesh) is stretched, and the mesh member 12 is applied to each of the gaps between the four columns 10 and the frame member 12a is fixed to the column 10 with a plurality of bolts. During maintenance of the antenna 6, the mesh member 12 can be removed from the support column by removing the bolts of any mesh member (see FIG. 3).

A metal protective cover 13 for protecting the control unit 5 is mounted on the mounting plate 11 of the support member 7. The protective cover 13 covers the entire control unit 5 to protect it from rainwater, dust, and the like. The protective cover 13 is formed in a cylindrical shape whose upper surface is closed, and is configured to accommodate the control unit 5 in a cylinder. .
The protective cover 13 is formed to have a smaller diameter than the mounting plate 11, and is provided with an overhanging portion 13 a that projects outward at a right angle on the opening peripheral edge on the lower end side. The overhanging portion 13 a can be fixed to the mounting plate 11 with a bolt (not shown) while being placed on the plate 11.

Further, on the lower end side of each support column 10 in the support member 7, a substrate 14 to which the lower end portions of these support columns 10 are fixed is disposed. The substrate 14 is formed in a plate shape having a substantially square shape in plan view, and one support column 10 is erected on each of the four corners of the substrate 14 along the corners.
Further, an opening 14a leading to the measurement hole 1c of the oil bunker 1 is opened at the center of the substrate 14, and the microwaves of the antenna 6 are emitted and received through the opening 14a. ing.
The substrate 14 in this embodiment is formed in a substantially rectangular shape in plan view with one side of the outer shape being about 330 mm and the opening 14a having a long side of 230 mm and a short side of about 170 mm.

By the way, the support member 7 is placed on a metal mounting table 15 installed at the periphery of the measurement hole 1c of the coal bunker 1, whereby the measurement hole 1c in the upper surface portion 1a of the coal bunker. It is fixed on the top.
The installation stand 15 can stably and reliably fix the support member 7 and thus the antenna 6 and the control unit 5 on the coal bunker 1 even in an environment where it is difficult to install the support member 7 on the coal bunker 1. As shown in FIGS. 1 and 4, the supporting member mounting portion 16 includes a mounting plate 16a having a substantially circular shape in plan view on which the supporting member 7 is mounted. And a base portion 17 installed on the upper surface portion 1a of the coal bunker 1 located at the lower stage of the placement portion 16, A communication hole 18 communicating with the measurement hole 1c of the bunker 1 is provided.
More specifically, the support member mounting portion 16 has a horizontal upper mounting plate 16a on which the support member 7 is mounted on the upper surface, and an upper end side fixed to the lower surface side center of the mounting plate 16a. And a cylindrical portion 16b having an outer diameter smaller than that of the mounting plate 16a, and an opening on the upper side of the communication hole 18 is opened at the center of the mounting plate 16a. The cylindrical portion 16 b is set to have the same inner diameter as the communication hole 18, and the inner peripheral surface of the cylindrical portion 16 b substantially constitutes the inner peripheral surface of the communication hole 18.
On the other hand, the base portion 17 is attached to a peripheral wall portion 19 erected so as to surround the measurement hole 1c of the coal bunker 1, and an upper end portion of the peripheral wall portion 19, and the cylinder is formed at the upper surface side center. And a connecting plate 20 to which the lower end side of the portion 16a is fixed. The peripheral wall portion 17 is configured by combining a total of four horizontally long plate bodies 19a and 19b, each of which is long and short, to form a substantially square space in plan view surrounding the measurement hole 1c. In the case shown in FIG. 4, ribs are formed on both ends in the longitudinal direction of the long plate 19a by disposing plate members of the same length at opposing positions. The portion 17 is reinforced. The connecting plate 20 is a substantially square plate body that is larger than the outer shape of the peripheral wall portion 19 in plan view, and protrudes outward from the peripheral wall portion 19. An opening on the lower side of the hole 18 is opened.

  In this embodiment, the installation table 15 has an outer diameter of about 550 mm, an inner diameter of the communication hole of about 400 mm, and a length per side of the space surrounded by the peripheral wall portion of about 690 mm. The length per side of the plate is about 800 mm, the height of the support member mounting portion is about 95 mm, and the height of the base portion is about 200 mm. An appropriate size can be obtained in consideration of the size of the bunker and the measurement hole, the size of the support member, and the like.

When the storage amount (measurement level) of coal in the coal bunker 1 is measured using the storage container level meter 4 having the above-described configuration, through the measurement hole 1c opened in the upper surface portion 1a of the coal bunker 1 The microwave is transmitted and received in the vertical direction from the control unit 5 via the antenna 6.
At this time, the level meter 4 supports the entire antenna 6 by supporting the entire antenna 6 on the coal bunker 1 with the support member 7 exposed to the atmosphere outside the coal bunker 1 on the measurement hole 1c. Since it is configured to be naturally ventilated by always touching the air in the atmosphere, it is possible to significantly suppress the occurrence of condensation on the antenna 6 as compared with the case where the conventional antenna is placed in a coal bunker with high humidity. Can do. Moreover, since the antenna 6 does not always and directly touch the atmosphere in the coal bunker 1, the environment itself in which moisture and dust in the coal bunker adhere to the antenna 6 is avoided.
As a result, it is possible to prevent a decrease in sensitivity of the antenna 6 due to dew condensation and to suppress the adhesion of dust by suppressing dew condensation, so that the sensitivity of the antenna 6 is always in a good state. The level of the contents in the coal bunker 1 can always be accurately measured.
Moreover, since the antenna 6 is always exposed to the air outside the coal bunker 1 as a storage container and naturally ventilates, the configuration is extremely simple compared to the case where water is forced out of the storage container by a machine or the like. Therefore, the manufacturing cost of the level meter can be suppressed.

  In the above embodiment, the case of a coal bunker is described as the storage container. It can be used to measure the storage amount of the contents of any storage container, such as a storage tank. In particular, it is suitable for measuring the storage amount of a storage container that stores a substance containing moisture.

  Moreover, although the example which measures the level of the content by a microwave is shown in the said embodiment, the structure which measures the level of the content by an ultrasonic wave may be sufficient. In this case, the configuration other than the control unit transmitting / receiving ultrasonic waves, for example, the configuration of the antenna, the support member, and the like is basically the same as that of the above-described embodiment.

  In the above embodiment, the support member 7 is configured to support the antenna 6 by the four support columns 10 and the mounting plate 11. However, even in other cases, the entire antenna is placed in the atmosphere outside the storage container on the measurement hole. Any structure may be used as long as it is supported on the storage container while being exposed inside, and an arbitrary support such as supporting the antenna in a state of stably projecting downward with one or five columns. A configuration can be used.

  Further, in the above embodiment, a cone type antenna is adopted, but this antenna is supported by the support member in a state where the whole antenna is exposed to the atmosphere outside the storage container on the measurement hole. If possible, a parabolic type may be used.

Further, in the above-described embodiment, the support column 10 is substantially L-shaped in plan view. However, as the support column, the plan view has an arbitrary shape such as a square shape, a circular shape, or a cylindrical shape. Things can be used.
Moreover, in the said embodiment, although the example which used the expanded metal as the mesh member 12 is shown in each space between adjacent support | pillars 10, this mesh member is made up of a plurality of linear materials in a rhombus shape or a lattice shape. Arbitrary metal meshes, perforated plates with large holes and excellent ventilation, resin nets, etc. can be used, or in some cases, the mesh member itself can be omitted. . In the case of the above embodiment, it is assumed that a wire mesh is attached in the frame material. However, it is not always necessary to configure in this way, and the wire mesh or the like may be stretched on the support as it is. is there.

  Furthermore, in the said embodiment, although the supporting member 7 is being fixed to the upper surface part 1a of the coal bunker 1 via the installation base 15, this installation base 15 does not necessarily need to be provided and a support member is stabilized. And if it can be reliably fixed on the storage container, it can be omitted. In addition, about this installation stand, the thing of a suitable form can be used according to the state of the upper surface part of a storage container, the size of a measurement hole, and the surrounding state, and it sets arbitrarily according to a situation. Can do.

It is sectional drawing of the level meter for storage containers which concerns on this invention. However, the case where it mounts on a coal bunker via an installation stand is shown. Moreover, the mesh member is omitted. It is principal part sectional drawing of the coal bunker which attached the level meter for storage containers which concerns on this invention. However, the mesh member is omitted. It is a perspective view from the lower side of the level meter for storage containers which concerns on this invention. It is a perspective view of an installation stand.

DESCRIPTION OF SYMBOLS 1 Coal bunker 1c Measurement hole 3 Coal 4 Storage container level meter 5 Control unit 6 Antenna 7 Support member 10 Prop 11 Mounting plate 12 Mesh member

Claims (3)

  A level meter that is mounted on a storage container and measures the storage level of the contents stored in the storage container through a measurement hole provided in the storage container, and transmits and receives microwaves and ultrasonic waves. A control unit having a function to perform, and an antenna that emits microwaves or ultrasonic waves transmitted from the control unit toward the contents, and receives the reflected waves reflected by the contents and causes the control unit to receive the reflected waves And a support member for supporting the antenna on the storage container in a state where the entire antenna is exposed to the atmosphere outside the storage container on the measurement hole.   The support member includes a plurality of upwardly extending columns arranged so as to surround the measurement hole, and a mounting plate that is attached to the upper ends of these columns and that fixes the antenna in a state of protruding downward. The level meter for a storage container according to claim 1, wherein The storage container level meter according to claim 2, wherein the support member has a mesh member attached to each space between adjacent columns.

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